ניתוח מימדי - בעיות ופתרונות
1. Based on the dimensional analysis, determine the following physics dimensions that have the same dimensions.
B. power and pressure
C. force and momentum
D. work and heat
ידוע:
Dimension of length = dimension of width = dimension of displacement = L
Dimension of time = T
Dimension of mass = M
פתרון:
Dimension of area = dimension of length x dimension of width = [L][L] = [L]2
Dimension of velocity = dimension of עקירה / dimension of time = [L] / [T] = [L][T]-1
Dimension of acceleration = dimension of velocity / dimension of time = [L][T]-1 / [T] = [L][T]-1[T]-1 = [L][T]-2
Dimension of force = dimension of mass x dimension of acceleration = [M][L][T]-2
Dimension of work = dimension of force x dimension of displacement = [M][L][T]-2 [L] = [M][L]2[T]-2
Dimension of power = dimension of work / dimension of time = [M][L]2[T]-2 / [T] = [M][L]2[T]-2[T]-1 = [M][L]2[T]-3
ממד של לחץ = dimension of force / dimension of area = [M][L][T]-2 / [L]2 = [M][L][T]-2 [L]-2 = [M] [L]-1[T]-2
מֵמַד of momentum = dimension of mass x dimension of velocity = [M][L][T]-1
Dimension of heat = dimension of energy = dimension of work = [M][L]2[T]-2
התשובה הנכונה היא D.
הערה:
חום is energy that moves due to the temperature difference.
Work is the process of energy transfer through the displacement of objects.
So, the dimension of heat = the dimension of energy = the dimension of work.
2. Two quantities that have the same quantity but have a different physical concept…
A. Force and momentum
B. Energy and force
C. Potential energy and kinetic energy
D. Energy and momentum
פתרון:
Unit of potential energy = unit of אנרגיה קינטית = unit of energy = unit of work.
Although it has the same unit, but the potential energy and the kinetic energy are different types of energy.
התשובה הנכונה היא C.
3. The following quantities that have the same units are…
A. Force and emf
B. Velocity and acceleration
C. עבודה ואנרגיה
D. Work and power
פתרון:
Work is the process of energy transfer through the displacement of objects.
Energy is the ability to do work.
Work and energy are two quantities of physics that have the same unit.
התשובה הנכונה היא C.
